Touching-type electronic paper and method for manufacturing the same

ABSTRACT

The present invention relates to a touching-type electronic paper and method for manufacturing the same. The touching-type electronic paper includes a TFT substrate and a transparent electrode substrate which are disposed as a cell. The transparent electrode substrate includes a common electrode, microcapsule electronic ink and light guiding poles as light transmitting passages, all of which are formed on a first substrate. The TFT substrate comprises displaying electrodes, first TFTs for driving the displaying electrodes, second TFTs for detecting lights transmitting through the light guiding poles and for producing level signals, and third TFTs for reading the level signals and sending the level signals to a back-end processing system, all of which are formed on a second substrate. The light guiding poles are opposite to the second TFTs respectively. The present invention makes the natural lights or other lights outside transmitted to the second TFTs through the light guiding poles by disposing the light guiding poles as light transmitting passages and disposing the second TFTs as light sensor units. The present invention has many advantages such as simple structure, simple manufacturing process and low cost, so as to have a wide application prospect.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No.200810240965.2, filed on Dec. 24, 2008, entitled “Touching-TypeElectronic Paper and Method for Manufacturing the Same”, which is herebyincorporated by reference in its entirety.

FIELD OF THE TECHNOLOGY

The present invention relates to an electronic paper and method formanufacturing the same, and particularly to a touching-type electronicpaper and method for manufacturing the same.

BACKGROUND

Electronic paper (E-Paper) is also called digital paper, which is aproduction combining an information displaying characteristic of generalpager with a characteristic of a computer display screen. Conventionalprinting productions are mainly accomplished by papers, so theenvironment is badly destroyed along with the papers are used more andmore. The electronic paper has the same characteristic with the papers,displaying, and could be used repeatedly, so it could not badly destroythe environment, and the electronic paper could display dynamitic image.Therefore, the electronic paper has a foreground to replace conventionalpaper documents soon. The electronic paper based on an electrophoretictechnology accomplishes displaying by electrophoretic phenomenon, ofwhich a working principle is to respectively drive color particleshaving positive or negative charge in microcapsule electronic ink tomove up and down by electric field, and black particles and whiteparticles respectively display black or white by reflecting andabsorbing natural lights. As the electrophoretic displaying technologytakes advantage of reflecting lights to display, energy consumption isvery low. Prior to now, as the advantages such as low energy consumptionand similar displaying effect with the papers, the electronic paperdisplaying technology based on the microcapsule electronic ink has awide application prospect.

A built-in type touch panel has gradually been a new developing trend ofa touch panel in recent years. The built-in type touch panel has theadvantages such as reducing complexity of manufacturing process,reducing displaying distortion, producing lighter and thinner productand so on by disposing sensors inside a display screen, for example,directly manufacturing on a thin film transistor (TFT) substrate. Basedon the display characteristic of the electronic paper, the naturallights are reflected and/or absorbed when they pass through themicrocapsule electronic ink, so they could not reach the TFT substrate.Therefore, there is not any technical solution to combine a lightsensing built-in type touch panel with the electronic paper in theconventional technology.

SUMMARY

The subject of the present invention is to provide a touching-typeelectronic paper and method for manufacturing the same, so as to combinea built-in type touch panel with an electronic paper organically, andmake the product have advantages such as simple structure, simplemanufacturing process, low cost and so on.

In order to accomplish the above subject, the present invention providesa touching-type electronic paper including a TFT substrate and atransparent electrode substrate disposed as a cell, wherein thetransparent electrode substrate includes a common electrode,microcapsule electronic ink and light guiding poles as lighttransmitting passages, all of which are formed on a first substrate; theTFT substrate includes displaying electrodes, first TFTs for driving thedisplaying electrodes respectively, second TFTs for detecting lightstransmitting through the light guiding poles and for producing levelsignals respectively, and third TFTs for reading the level signals andsending the level signals to a back-end processing system, all of whichare formed on a second substrate; and the light guiding poles areopposite to the second TFTs respectively.

The common electrode is formed on the first substrate, the light guidingpoles made of transparent material are formed on the common electrode,and the other part of the common electrode where no light guiding poleis coated with the microcapsule electronic ink. A height of the lightguiding poles is 35%-65% of a distance between the TFT substrate and thetransparent electrode substrate. Preferably, the height of the lightguiding poles is 50% of the distance between the TFT substrate and thetransparent electrode substrate.

Each of the first TFTs includes:

a first gate electrode formed on the second substrate and connected to afirst gate line;

a gate insulation layer formed on the first gate electrode and coveringthe entire second substrate;

a first active layer including a semiconductor layer and a dopedsemiconductor layer, formed on the gate insulation layer and locatedover the first gate electrode;

a first source electrode, of which one end is located on the firstactive layer and the other end is connected to a data line;

a first drain electrode, of which one end is located on the first activelayer and the other end is connected to the displaying electrode;

a first TFT channel region, formed between the first source electrodeand the first drain electrode, wherein the doped semiconductor layerbetween the first source electrode and the first drain electrode isentirely etched off to expose the semiconductor layer; and

a passivation layer formed on the first source electrode and the firstdrain electrode, covering the entire second substrate and provided witha passivation layer via hole for connecting the displaying electrode andthe first drain electrode.

Each of the second TFTs includes:

a second gate electrode formed on the second substrate and connected toa second gate line;

a gate insulation layer formed on the second gate electrode and coveringthe entire second substrate;

a second active layer including a semiconductor layer and a dopedsemiconductor layer, formed on the gate insulation layer and locatedover the second gate electrode;

a second source electrode, of which one end is located on the secondactive layer, and the other end is connected to a power line;

a second drain electrode, of which one end is located on the secondactive layer and the other end is connected to a third source electrodeof each third TFT;

a second TFT channel region formed between the second source electrodeand the second drain electrode, wherein the doped semiconductor layerbetween the second source electrode and the second drain electrode isentirely etched off to expose the semiconductor layer; and

a passivation layer formed on the second source electrode and the seconddrain electrode and covering the entire second substrate.

Each of the third TFTs includes:

a third gate electrode formed on the second substrate and connected to athird gate line;

a gate insulation layer formed on the third gate electrode and coveringthe entire second substrate;

a third active layer including a semiconductor layer and a dopedsemiconductor layer, formed on the gate insulation layer and locatedover the third gate electrode;

a third source electrode, of which one end is located on the thirdactive layer and the other end is connected to a second drain electrodeof each second TFT;

a third drain electrode, of which one end is located on the third activelayer and the other end is connected to a signal line;

a third TFT channel region formed between the third source electrode andthe third drain electrode, wherein the doped semiconductor layer betweenthe third source electrode and the third drain electrode is entirelyetched off to expose the semiconductor layer; and

a passivation layer formed on the third source electrode and the thirddrain electrode and covering the entire second substrate.

In order to accomplish the above subject, the present invention furtherprovides a method for manufacturing touching-type electronic paper. Themethod includes the following steps:

manufacturing a transparent electrode substrate including a commonelectrode and light guiding poles as light transmitting passages whichare all formed on a first substrate;

manufacturing a TFT substrate including a displaying electrode, firstTFTs as driving units, second TFTs as light sensor units and third TFTsas signal reading units, which are all formed one a second substrate;and

disposing the transparent electrode substrate and the TFT substrate as acell, in which the light guiding poles are opposite to the second TFTsrespectively.

The step of manufacturing the transparent electrode substrate includesthe following steps:

forming the common electrode on the first substrate;

forming the light guiding poles as light transmitting passages on thecommon electrode; and

coating the other part of the common electrode where no light guidingpole with microcapsule electronic ink.

The step of manufacturing the TFT substrate includes the followingsteps:

depositing a gate metal film on a substrate, and forming a patternincluding first gate lines, second gate lines, third gate lines, commonelectrode lines, first gate electrodes, second gate electrodes and thirdgate electrodes by a patterning process, in which each first gateelectrode is connected to each first gate line, each second gateelectrode is connected to each second gate line, and each third gateelectrode is connected to each third gate line respectively;

depositing orderly a gate insulation layer, a semiconductor layer and adoped semiconductor layer on the substrate containing the above pattern,and forming a pattern including the first active layers, the secondactive layers and the third active layers by a pattering process, inwhich each first active layer is located over each first gate electrode,each second active layer is located over each second gate electrode, andeach third active layer is located over each third gate electroderespectively;

depositing a source/drain metal film on the substrate containing theabove patterns, and forming a pattern including data lines, power lines,signal lines, first source electrodes, first drain electrodes, first TFTchannel regions, second source electrodes, second drain electrodes,second TFT channel regions, third source electrodes, third drainelectrodes and third TFT channel regions by a patterning process, inwhich each second drain electrode is connected to each third sourceelectrode respectively;

depositing a passivation layer on the substrate containing the abovepatterns, and forming a patterns including passivation layer via holesby a patterning process, in which each passivation layer via hole islocated over each first drain electrode respectively; and

depositing a transparent conducting film on the substrate containing theabove patterns, and forming a pattern including displaying electrodes indisplaying regions respectively by a patterning process, in which eachdisplaying electrode is connected to each first drain electrode througheach passivation layer via hole respectively.

Based on the above technical solution, a height of the light guidingpoles is 35%-65% of a distance between the TFT substrate and thetransparent electrode substrate. Preferably, the height of the lightguiding poles is 50% of the distance between the TFT substrate and thetransparent electrode substrate.

The present invention provides a touching-type electronic paper andmethod for manufacturing the same. By disposing the light guiding poleson the transparent electrode substrate as light transmitting passagesand disposing the second TFTs on the TFT substrate as light sensorunits, the present invention makes the natural lights or other lightsoutside transmitted to the second TFTs through the light guiding poles,and combines a built-in touch panel with an electronic paperorganically, thereby solving with the technical problem that lightsensor can not be used to make a touch panel because the natural lightscan not reach the TFT substrate when the electronic paper aredisplaying. The present invention has many advantages such as simplestructure, simple manufacturing process and low cost, so as to have awide application prospect.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structure view of a touching-type electronic paperaccording to the present invention;

FIG. 2 is a schematic structure view of a first TFT according to thepresent invention;

FIG. 3 is a schematic structure view of a second TFT and a third TFTaccording to the present invention;

FIG. 4 is a flow chart of a method for manufacturing a touching-typeelectronic paper according to the present invention;

FIG. 5 is a flow chart of manufacturing a transparent electrodesubstrate in a method for manufacturing a touching-type electronic paperaccording to the present invention;

FIG. 6 is a flow chart of manufacturing a TFT substrate in a method formanufacturing a touching-type electronic paper according to the presentinvention;

FIG. 7 is a schematic view of a first patterning process in the step ofmanufacturing a TFT substrate according to the present invention;

FIG. 8 is a schematic view of a second patterning process in the step ofmanufacturing a TFT substrate according to the present invention;

FIG. 9 is a schematic view of a third patterning process in the step ofmanufacturing a TFT substrate according to the present invention;

FIG. 10 is a schematic view of a fourth patterning process in the stepof manufacturing a TFT substrate according to the present invention; and

FIG. 11 is a schematic view of a fifth patterning process in the step ofmanufacturing a TFT substrate according to the present invention.

In the drawings:

11 first substrate 12 common electrode 13 light guiding pole 14microcapsule electronic ink 21 second substrate 22 displaying electrode23 first TFT 24 second TFT 25 third TFT 26 gate insulation layer 27semiconductor layer 28 doped semiconductor layer 29 passivation layer231 first gate electrode 232 first source electrode 233 first drainelectrode 241 second gate electrode 242 second source electrode 243second drain electrode 251 third gate electrode 252 third sourceelectrode 253 third drain electrode 291 passivation layer via hole 100transparent electrode substrate 200 TFT substrate

DETAILED DESCRIPTION

In order to make the objects, technical solutions and merits of thepresent invention clearer, a further detailed description of embodimentsof the present invention is given by reference to accompanying drawings.

FIG. 1 is a schematic structure view of a touching-type electronic paperaccording to the present invention. As shown in FIG. 1, the principalstructure of the touching-type electronic paper in the present inventionincludes a transparent electrode substrate 100 and a TFT substrate 200.The transparent electrode substrate 100 and the TFT substrate 200 aredisposed and sealed as a cell to be the touching-type electronic paperin the present invention. The transparent electrode substrate 100includes a common electrode 12, light guiding poles 13 and microcapsuleelectronic ink 14 formed on a first substrate 11. The common electrode12 is formed on the first substrate 11. The light guiding poles 13 areformed on the common electrode 12, and are transparent structures takenas light transmitting passages to make the natural lights outside thetransparent electrode substrate 100 to be transmitted to the TFTsubstrate 200 through the light guiding poles 13. The common electrode12 is also coated with the microcapsule electronic ink 14. Particularly,the other part of the common electrode 12 where no light guiding pole iscoated with the microcapsule electronic ink 14. The TFT substrate 200includes displaying electrodes 22, first TFTs 23, second TFTs 24 andthird TFTs 25 formed on a second substrate 21. The displaying electrodes22 are formed on the second substrate 21, and used for forming anelectric field with the common electrode 12 on the transparent electrodesubstrate 100 to drive the microcapsule electronic ink 14. The firstTFTs 23 are formed on the second substrate 21, which are taken asdriving units and used for controlling the voltages of the displayingelectrodes 22. The second TFTs 24 are formed on the second substrate 21,which are taken as light sensor units and used for detecting lightstransmitting through the light guiding poles 13 and for producing levelsignals corresponding to the change of the lights. The second TFTs 24are opposite to the light guiding poles 13 on the transparent electrodesubstrate 100, that is, the position of the light guiding poles 13 aimsat the position of the second TFTs 24. The third TFTs 25 are also formedon the second substrate 21, which are taken as signal reading units andused for reading the level signals of the second TFTs 24 and sending thelevel signals to a back-end processing system, so as to finally obtain aposition of touching point to control displaying of the electronicpaper.

In the above technical solution of the present invention, the firstsubstrate of the transparent electrode substrate may be made of atransparent substrate such as a glass substrate or a quartz substrate.The common electrode may be made of a conducting film such as indium tinoxide (ITO) or indium zinc oxide (IZO), and may be deposited by amagnetron sputtering method or a thermal evaporation method. The lightguiding poles may be made of a transparent material. The structural ofthe light guiding poles is similar to the structural of a post spacer(PS) in the conventional liquid crystal display, which are formed by apattering process. In a particular application, the height of the lightguiding poles in the present invention may be set to be 35%-65% of thedistance between the TFT substrate and the transparent electrodesubstrate, that is, the height of the light guiding poles is 35%-65% ofa cell thickness of the touching-type electronic paper in the presentinvention. Preferably, the height of the light guiding poles is 50% ofthe distance between the TFT substrate and the transparent electrodesubstrate.

In the above technical solution of the present invention, the TFTsubstrate includes first gate lines, second gate lines, third gatelines, common electrode lines, data lines, power lines, signal lines,displaying electrodes, the first TFTs as driving units, the second TFTsas light sensor units and the third TFTs as signal reading units.Particularly, the first gate lines and the data lines define thedisplaying regions together. The first TFTs are formed at theintersections of the first gate lines and the data lines respectively.The second TFTs are formed at the intersections of the second gate linesand the power lines respectively. The third TFTs are formed at theintersections of the third gate lines and the signal lines respectively.The displaying electrodes are formed in the displaying regionsrespectively. The common electrode lines (also called storage capacitorlines) are also formed in the displaying regions respectively, and arelocated between two first gate lines. The common electrode lines areused for forming storage capacitors together with the displayingelectrodes.

FIG. 2 is a schematic structure view of a first TFT according to thepresent invention. As shown in FIG. 2, each of the first TFTs includes afirst gate electrode 231, a gate insulation layer 26, a first activelayer (including a semiconductor layer 27 and a doped semiconductorlayer 28), a first source electrode 232, a first drain electrode 233 anda passivation layer 29. Each first gate electrode 231 is formed on thesecond substrate 21 and is connected to each first gate line. The gateinsulation layer 26 is formed on first gate electrodes 231 and coversthe entire second substrate 21. Each first active layer is formed on thegate insulation layer 26 and is located over each first gate electrode231. One end of each first source electrode 232 is located on each firstactive layer, and the other end of each first source electrode 232 isconnected to each data line respectively. One end of each first drainelectrode 233 is located on the first active layer, and the other end ofeach first drain electrode 233 is connected to each displaying electrode22 through each passivation layer via hole respectively. A TFT channelregion is formed between each first source electrodes 232 and each firstdrain electrode 233. The doped semiconductor layer 28 inside of eachfirst TFT channel region is etched off entirely and part of thickness ofeach semiconductor layer 27 is also etched off. The passivation layer 29is formed on first TFT channel regions and covers the entire secondsubstrate 21. The passivation layer 29 is provided with passivationlayer via holes which are used for connecting the displaying electrodes22 and the first drain electrodes 233 respectively. The structural ofthe first TFTs in the present invention is substantially same as thestructural of TFTs in the conventional liquid crystal display.

FIG. 3 is a schematic structure view of one second TFT and one third TFTaccording to the present invention. As shown in FIG. 3, each of thesecond TFTs includes a second gate electrode 241, a gate insulationlayer 26, a second active layer (including a semiconductor layer 27 anda doped semiconductor layer 28), a second source electrode 242, a seconddrain electrode 243 and a passivation layer 29. Each second gateelectrode 241 is formed on the second substrate 21 and is connected toeach second gate line. The gate insulation layer 26 is formed on eachsecond gate electrode 241 and covers the entire second substrate 21.Each second active layer is formed on the gate insulation layer 26 andis located over each second gate electrode 241. One end of each secondsource electrode 242 is located on the second active layer, and theother end of each second source electrode 242 is connected to each powerline respectively. One end of each second drain electrode 243 is locatedon each second active layer, and the other end of each second drainelectrode 243 is connected to the third source electrode 252 of eachthird TFT respectively. A second TFT channel region is formed betweeneach second source electrode 242 and each second drain electrode 243respectively. The doped semiconductor layer 28 inside of each second TFTchannel region is etched off entirely, and part of thickness of eachsemiconductor layer 27 is also etched off. The passivation layer 29 isformed on second TFT channel regions and covers the entire secondsubstrate 21. The power lines are used for providing voltage signals tothe second source electrodes 242 respectively, the second TFT channelregions are used for detecting the change of lights to make each secondsource electrode 242 and each second drain electrode 243 conductive ornot.

Each of the third TFTs includes a third gate electrode 251, a gateinsulation layer 26, a third active layer (including a semiconductorlayer 27 and a doped semiconductor layer 28), a third source electrode252, a third drain electrode 253 and a passivation layer 29. Each thirdgate electrode 251 is formed on the second substrate 21 and is connectedto each third gate line respectively. The gate insulation layer 26 isformed on each third gate electrode 251 and covers the entire secondsubstrate 21. Each third active layer is formed on the gate insulationlayer 26 and is located over each third gate electrode 251 respectively.One end of each third source electrode 252 is located on each thirdactive layer, and the other end of each third source electrode 252 isconnected to the second drain electrode 243 of each second TFTrespectively. One end of each third drain electrode 253 is located oneach third active layer, and the other end of each third drain electrode253 is connected to each signal line respectively. A third TFT channelregion is formed between each third source electrode 252 and each thirddrain electrode 253 respectively. Each signal line is used for sendingthe level signal of each second TFT to the back-end processing system.

The working principle of the touching-type electronic paper in thepresent invention is specifically as following: when there is not anytouch-matter touching the surface of the touching-type electronic paperin the present invention, the natural lights or other lights outside thetransparent electrode substrate are transmitted to the second TFTs onthe TFT substrate through the light guiding poles on the transparentelectrode substrate, and the concentration of the photo-induced carriersin each second TFT is not changed; when there is touch-matter such as afinger sweeping the surface of the touching-type electronic paper in thepresent invention, the natural lights or other lights outside thetransparent electrode substrate are held up, which makes the naturallights or other lights can not reach the second TFT on the TFTsubstrate, and the concentration of the photo-induced carriers in thesecond TFT is changed, which makes the level signal of the second TFTchanged, and the back-end processing system could make certain theposition of the touching point by analyzing the level signal, so as tocontrol the displaying of the electronic paper.

The working principle of the first TFTs in the present invention is thesame as the TFT of the conventional liquid crystal display, which isunnecessary to go into details. Each second gate line provides a cuttingvoltage to the second gate electrode of each second TFT in the presentinvention and each power line provides a forward high level to eachsource electrode. When there is not any touch-matter touching thesurface of the touching-type electronic paper in the present invention,as the natural lights or other lights outside could reach the second TFTchannel regions of the second TFTs through the light guiding poles,photo-induced carriers could be produced in the semiconductor layers ofthe second TFT channel regions. Although the second gate electrodesprovide the cutting voltage at this time, the photo-induced carriersexisting in the semiconductor layers make the second source electrodesand the second drain electrodes of the second TFTs conducted. Therefore,the second drain electrodes are provided a high level equal to that ofthe second source electrodes. When a touch-matter such as the fingersweeping the surface of the touching-type electronic paper in thepresent invention, the natural lights or other lights outside thetransparent electrode substrate are held up, which makes the naturallights or other lights can not reach the second TFT on the TFTsubstrate, and the photo-induced carriers in the semiconductor layer ofthe second TFT channel region is disappeared. Therefore under thecutting voltage of the second gate electrode, the second sourceelectrode and the second drain electrode of the second TFT could not beconductive. At this time, the level of the second drain electrode isreduced to be a low level. The third gate electrode of each third TFT inthe present invention is provided with a turn-on voltage by each thirdgate line, which makes the third source electrode and the third drainelectrode of the third TFT maintain a conduction status. As the sourceelectrode of each third TFT is connected to the second drain electrodeof each second TFT, the change of level of the second drain electrode inthe second TFT could be outputted to each signal line by the third drainelectrode of each third TFT. The back-end process system could analyzeand process according to the change of the level, so as to finallyobtain the position of the touching point and control the displaying ofthe electronic paper. It can be seen that the present invention has manyadvantages such as simple structure, simple manufacturing process andlow cost, and has a wide application prospect.

FIG. 4 is a flow chart of a method for manufacturing a touching-typeelectronic paper according to the present invention. The methodspecifically includes the following steps.

In step 1, a transparent electrode substrate is manufactured, and thetransparent electrode substrate includes a common electrode and lightguiding poles as light transmitting passages, which are formed on afirst substrate.

In step 2, a TFT substrate is manufactured, and TFT substrate includesdisplaying electrodes, first TFTs as driving units, second TFTs as lightsensor units and third TFTs as signal reading units, which are formed ona second substrate.

In step 3, the transparent electrode substrate and the TFT substrate aredisposed as a cell, in which the light guiding poles are opposite to thesecond TFTs respectively.

It should be explained that, in the method for manufacturing thetouching-type electronic paper in the present invention, the step 1 andstep 2 are independent manufacturing processes, and there is not anyorder relationship between the two steps. The step 1 and step 2 could beexecuted based on any order according to particular demand.

FIG. 5 is a flow chart of manufacturing a transparent electrodesubstrate in a method for manufacturing a touching-type electronic paperaccording to the present invention. The method specifically includes thefollowing steps.

In step 11, a common electrode is formed on the first substrate.

In step 12, light guiding poles as the light transmitting passages areformed on the common electrode.

In step 13, the other part of the common electrode where no lightguiding poles is coated with the microcapsule electronic ink.

During the step of manufacturing the transparent electrode substrate,the first substrate may be made of a transparent substrate such as aglass substrate or a quartz substrate; the common electrode is formed bya magnetron sputtering method or a thermal evaporation method, thecommon electrode may be made of a conductor film such as ITO or IZO. Themanufacturing method for forming light guiding poles on the commonelectrode is the same as the method for manufacturing the post spacersof the conventional liquid crystal display. The structural of the lightguiding poles made of transparent material is similar to the structuralof the post spacers in the conventional liquid crystal display. Finally,by coating the other part of the common electrode where no light guidingpole with the microcapsule electronic ink, and by sealing themicrocapsule electronic ink to manufacture the transparent electrodesubstrate in the present invention. The height of the light guidingpoles in the present invention may be set to be 35%-65% of the distancebetween the TFT substrate and the transparent electrode substrate, thatis, the height of the light guiding poles is 35%-65% of a cell thicknessof the touching-type electronic paper in the present invention.Preferably, the height of the light guiding poles is 50% of the distancebetween the TFT substrate and the transparent electrode substrate.

FIG. 6 is a flow chart of manufacturing a TFT substrate in a method formanufacturing a touching-type electronic paper according to the presentinvention. The method specifically includes the following steps.

In step 21, a gate metal film is deposited on a substrate, and a patternincluding first gate lines, second gate lines, third gate lines, commonelectrode lines, first gate electrodes, second gate electrodes and thirdgate electrodes is formed by a patterning process, in which each firstgate electrode is connected to each first gate line, each second gateelectrode is connected to each second gate line, and each third gateelectrode is connected to each third gate line respectively.

In step 22, the gate insulation layer, a semiconductor layer and a dopedsemiconductor layer are orderly deposited on the substrate afterfinishing the step 21, and a pattern including the first active layers,the second active layers and the third active layers is formed by apattering process, in which each first active layer is located over eachfirst gate electrode, each second active layer is located over eachsecond gate electrode, and each third active layer is located over eachthird gate electrode.

In step 23, a source/drain metal film is deposited on the substrateafter finishing the step 22, and a pattern including data lines, powerlines, signal lines, first source electrodes, first drain electrodes,first TFT channel regions, second source electrodes, second drainelectrodes, second TFT channel regions, third source electrodes, thirddrain electrodes and third TFT channel regions is formed by a patterningprocess, in which each second drain electrode is connected to each thirdsource electrode respectively.

In step 24, a passivation layer is deposited on the substrate afterfinishing the step 23, and a pattern including passivation layer viaholes is formed by a patterning process, in which each passivation layervia hole is located over each first drain electrode respectively.

In step 25, a transparent conducting film is deposited on the substrateafter finishing the step 24, and a pattern including displayingelectrodes in displaying regions is formed by a patterning process, inwhich each displaying electrode is connected to each first drainelectrode through each passivation layer via hole respectively.

FIG. 7 is a schematic view of a first patterning process in the step ofmanufacturing a TFT substrate according to the present invention. Instep 21, firstly, a layer of gate metal film is deposited on the secondsubstrate (for example a glass substrate or a quartz substrate) 21 by amagnetron sputtering method or a thermal evaporation method. The gatemetal film may be made of metal such as molybdenum, aluminum, aluminumnickel alloy, molybdenum tungsten alloy, chromium or copper, or may be amultilayer metal film structure composed of the above several materials.The gate metal film is patterned by a first pattering process using ageneral mask, so as to form the pattern including the first gate lines,the second gate lines, the third gate lines, the common electrode lines,the first gate electrodes 231, the second gate electrodes 241 and thethird gate electrodes 251, as shown in FIG. 7. The first gate electrodes231, the second gate electrodes 241 and the third gate electrodes 251are taken as gate electrodes of the first TFTs, the second TFTs and thethird TFTs. Each first gate electrode 231 is connected to each firstgate line respectively, each second gate electrode 241 is connected toeach second gate line respectively, and each third gate electrode 251 isconnected to each third gate line respectively.

FIG. 8 is a schematic view of a second patterning process in the step ofmanufacturing a TFT substrate according to the present invention. Instep 22, on the substrate containing the above pattern, the gateinsulation layer 26, the semiconductor layer 27 and the dopedsemiconductor layer 28 are deposited orderly by plasma enhanced chemicalvapor deposition (PECVD) method. The semiconductor layer 27 and thedoped semiconductor layer 28 are patterned by the second patteringprocess using a general mask, so as to form the pattern including thefirst active layers, the second active layers and the third activelayers. Each active layer includes a semiconductor layer 27 and a dopedsemiconductor layer 28, as shown in FIG. 8. Each first active layer isformed over each first gate electrode 231 respectively, each secondactive layer is formed over each second gate electrode 241 respectively,and each third active layer is formed over each third gate electrode 251respectively.

FIG. 9 is a schematic view of a third patterning process in the step ofmanufacturing a TFT substrate according to the present invention. Instep 23, on the substrate containing the above pattern, a layer ofsource/drain metal film is deposited by a magnetron sputtering method ora thermal evaporation method. The source/drain metal film may be made ofmetals such as molybdenum, aluminum, aluminum nickel alloy, molybdenumtungsten alloy, chromium or copper, or may be multilayer metal filmstructure composed of the above several materials. The source/drainmetal film is patterned by a third pattering process using a generalmask, so as to form the pattern including the data lines, the powerlines, the signal lines, the first source electrodes 232, the firstdrain electrodes 233, the second source electrodes 242, the second drainelectrodes 243, the third source electrodes 252 and the third drainelectrodes 253 at the same time, as shown in FIG. 9. One end of eachfirst source electrode 232 is located on each first active layer, andthe other end of each first source electrode 232 is connected to eachdata line. One end of each first drain electrode 233 is located on eachfirst active layer, and the other end of each first drain electrode 233is connected to each displaying electrode. The first TFT channel regionis formed between each first source electrode 232 and each first drainelectrode 233. The doped semiconductor layer 28 inside of each first TFTchannel region is etched off entirely and part of thickness of eachsemiconductor layer 27 is also etched off. One end of each second sourceelectrode 242 is located on each second active layer, and the other endof each second source electrode 242 is connected to each power line. Oneend of each second drain electrode 243 is located on each second activelayer, and the other end of each second drain electrode 243 is connectedto each third source electrode 252. The second TFT channel region isformed between each second source electrode 242 and each second drainelectrode 243. The doped semiconductor layer 28 inside of each secondTFT channel region is etched off entirely, and part of thickness of eachsemiconductor layer 27 is also etched off. The power lines are used forproviding voltage signals to the second source electrodes 242, thesecond TFT channel regions are used for detecting the change of lightsto make each second source electrode 242 and each second drain electrode243 conductive or not. One end of each third source electrode 252 islocated on each third active layer, and the other end of each thirdsource electrode 252 is connected to the second drain electrode 243. Oneend of each third drain electrode 253 is located on each third activelayer, and the other end of each third drain electrode 253 is connectedto each signal line. The third TFT channel region is formed between eachthird source electrode 252 and each third drain electrode 253. The dopedsemiconductor layer 28 inside of each third TFT channel region is etchedoff entirely, and part of thickness of each semiconductor layer 27 isalso etched off. Each signal line is used for sending the level signalto the back-end processing system.

FIG. 10 is a schematic view of a fourth patterning process in the stepof manufacturing a TFT substrate according to the present invention. Instep 24, on the substrate containing the above pattern, a passivationlayer 29 is deposited by a PECVD method. The passivation layer 29 may bemade of silicon nitride, silicon oxide or silicon oxynitride and so on.The passivation layer 29 is patterned by a fourth pattering processusing a general mask, so as to form the pattern including thepassivation layer via holes 291. Each passivation layer via hole 291 islocated over each first drain electrode 233 respectively, as shown inFIG. 10. In this pattering process, first gate line pads, second gateline pads, third gate line pads, data line pads, power line pads, signalline pads and common electrode line pads are formed at the same time.The process of forming the pads by the pattering process using a generalmask has been widely applied in the conventional pattering process, itis unnecessary to go into details.

FIG. 11 is a schematic view of a fifth patterning process in the step ofmanufacturing a TFT substrate according to the present invention. Instep 25, on the substrate containing the above pattern, a layer oftransparent conducting film is deposited by a magnetron sputteringmethod or a thermal evaporation method. The transparent conducting filmmay be made of ITO, IZO or aluminum zinc oxide (AZO) and so on. Thetransparent conducting film is patterned by the fifth pattering processusing a general mask, so as to form the pattern including the displayingelectrodes 22 in the displaying regions. Each displaying electrode 22 isconnected to each first drain electrode 233 through each passivationlayer via hole respectively, as shown in FIG. 11.

The five pattering processes described above is only one accomplishingmethod for manufacturing the TFT substrate in the present invention. Inparticular application, the present invention may be also accomplishedby adding or reducing one or more of the pattering processes, or byselecting different material or material compound. For example, theabove second pattering process and the third pattering process may becombined as one pattering process, and the TFT substrate in the presentinvention could be formed by multi-step etching processes.

The step of disposing the transparent electrode substrate and the TFTsubstrate as a cell includes procedures of sealant coating, assemblingand so on, It may be any assembling method in the conventional liquidcrystal display manufacture to ensure each light guiding pole on thetransparent electrode substrate aiming at each second TFT on the TFTsubstrate. And then the natural lights outside the transparent electrodesubstrate may transmit to the TFT channel regions of the second TFTsthrough the light guiding poles.

The present invention provides a touching-type electronic paper andmethod for manufacturing the same. The present invention makes thenatural lights or other lights outside transmitted to the second TFTs ofthe TFT substrate through the light guiding poles by disposing the lightguiding poles as light transmitting passages on the transparentelectrode substrate and disposing the second TFTs as light sensor unitson the TFT substrate, which combines a built-in type touch panel with anelectronic paper organically, thereby solving the technical problem thatlight sensor can not be used in a touching-type electronic paper panelbecause the natural lights can not reach the TFT substrate. The presentinvention has many advantages such as simple structure, simplemanufacturing process and low cost, so as to have a wide applicationprospect.

Finally, it should be noted that the above embodiments are merelyprovided for describing the technical solutions of the presentinvention, but not intended to limit the present invention. It should beunderstood by those of ordinary skill in the art that although thepresent invention has been described in detail with reference to theforegoing embodiments, modifications can be made to the technicalsolutions described in the foregoing embodiments, or equivalentreplacements can be made to some technical features in the technicalsolutions, as long as such modifications or replacements do not causethe essence of corresponding technical solutions to depart from thescope of the present invention.

1. A touching-type electronic paper, comprising a thin film transistor(TFT) substrate and a transparent electrode substrate disposed as acell, wherein the transparent electrode substrate comprises a commonelectrode, microcapsule electronic ink and light guiding poles as lighttransmitting passages, all of which are formed on a first substrate; theTFT substrate comprises displaying electrodes, first TFTs for drivingthe displaying electrodes respectively, second TFTs for detecting lightstransmitting through the light guiding poles and for producing levelsignals respectively, and third TFTs for reading the level signals andsending the level signals to a back-end processing system, all of whichare formed on a second substrate; and the light guiding poles areopposite to the second TFTs respectively.
 2. The touching-typeelectronic paper according to claim 1, wherein the common electrode isformed on the first substrate, the light guiding poles made oftransparent material are formed on the common electrode, and the otherpart of the common electrode where no light guiding pole is coated withthe microcapsule electronic ink.
 3. The touching-type electronic paperaccording to claim 1, wherein a height of the light guiding poles is35%-65% of a distance between the TFT substrate and the transparentelectrode substrate.
 4. The touching-type electronic paper according toclaim 3, wherein the height of the light guiding poles is 50% of thedistance between the TFT substrate and the transparent electrodesubstrate.
 5. The touching-type electronic paper according to claim 1,wherein each of the first TFTs comprises: a first gate electrode formedon the second substrate and connected to a first gate line; a gateinsulation layer formed on the first gate electrode and covering theentire second substrate; a first active layer comprising a semiconductorlayer and a doped semiconductor layer, formed on the gate insulationlayer and located over the first gate electrode; a first sourceelectrode, of which one end is located on the first active layer and theother end is connected to a data line; a first drain electrode, of whichone end is located on the first active layer and the other end isconnected to the displaying electrode; a first TFT channel region formedbetween the first source electrode and the first drain electrode,wherein the doped semiconductor layer between the first source electrodeand the first drain electrode is entirely etched off to expose thesemiconductor layer; and a passivation layer formed on the first sourceelectrode and the first drain electrode, covering the entire secondsubstrate and provided with a passivation layer via hole for connectingthe displaying electrode and the first drain electrode.
 6. Thetouching-type electronic paper according to claim 1, wherein each of thesecond TFTs comprises: a second gate electrode formed on the secondsubstrate and connected to a second gate line; a gate insulation layerformed on the second gate electrode and covering the entire secondsubstrate; a second active layer comprising a semiconductor layer and adoped semiconductor layer, formed on the gate insulation layer andlocated over the second gate electrode; a second source electrode, ofwhich one end is located on the second active layer and the other end isconnected to a power line; a second drain electrode, of which one end islocated on the second active layer and the other end is connected to athird source electrode of each third TFT; a second TFT channel regionformed between the second source electrode and the second drainelectrode, wherein the doped semiconductor layer between the secondsource electrode and the second drain electrode is entirely etched offto expose the semiconductor layer; and a passivation layer formed on thesecond source electrode and the second drain electrode and covering theentire second substrate.
 7. The touching-type electronic paper accordingto claim 1, wherein each of the third TFTs comprises: a third gateelectrode formed on the second substrate and connected to a third gateline; a gate insulation layer formed on the third gate electrode andcovering the entire second substrate; a third active layer comprising asemiconductor layer and a doped semiconductor layer, formed on the gateinsulation layer and located over the third gate electrode; a thirdsource electrode, of which one end is located on the third active layerand the other end is connected to a second drain electrode of eachsecond TFT; a third drain electrode, of which one end is located on thethird active layer and the other end is connected to a signal line; athird TFT channel region formed between the third source electrode andthe third drain electrode, wherein the doped semiconductor layer betweenthe third source electrode and the third drain electrode is entirelyetched off to expose the semiconductor layer; and a passivation layerformed on the third source electrode and the third drain electrode andcovering the entire second substrate.
 8. A method for manufacturingtouching-type electronic paper, comprising: manufacturing a transparentelectrode substrate comprising a common electrode and light guidingpoles as light transmitting passages which are all formed on a firstsubstrate; manufacturing a thin film transistor (TFT) substratecomprising a displaying electrode, first TFTs as driving units, secondTFTs as light sensor units and third TFTs as signal reading units, whichare all formed on a second substrate; and disposing the transparentelectrode substrate and the TFT substrate as a cell, in which the lightguiding poles are opposite to the second TFTs respectively.
 9. Themethod according to claim 8, wherein manufacturing the transparentelectrode substrate comprises: forming the common electrode on the firstsubstrate; forming the light guiding poles as the light transmittingpassages on the common electrode; and coating the other part of thecommon electrode where no light guiding pole with the microcapsuleelectronic ink.
 10. The method according to claim 8, whereinmanufacturing the TFT substrate comprises: depositing a gate metal filmon a substrate, and forming a pattern comprising first gate lines,second gate lines, third gate lines, common electrode lines, first gateelectrodes, second gate electrodes and third gate electrodes by apatterning process, in which each first gate electrode is connected toeach first gate line, each second gate electrode is connected to eachsecond gate line, and each third gate electrode is connected to eachthird gate line respectively; depositing orderly a gate insulationlayer, a semiconductor layer and a doped semiconductor layer on thesubstrate containing the above pattern, and forming a pattern comprisingthe first active layers, the second active layers and the third activelayers by a pattering process, in which each first active layer islocated over each first gate electrode, each second active layer islocated over each second gate electrode, and each third active layer islocated over each third gate electrode respectively; depositing asource/drain metal film on the substrate containing the above patterns,and forming a pattern comprising data lines, power lines, signal lines,first source electrodes, first drain electrodes, first TFT channelregions, second source electrodes, second drain electrodes, second TFTchannel regions, third source electrodes, third drain electrodes andthird TFT channel regions by a patterning process, in which each seconddrain electrode is connected to each third source electroderespectively; depositing a passivation layer on the substrate containingthe above patterns, and forming a patterns comprising passivation layervia holes by a patterning process, in which each passivation layer viahole is located over each first drain electrode respectively; anddepositing a transparent conducting film on the substrate containing theabove patterns, and forming a pattern comprising displaying electrodesin displaying regions respectively by a patterning process, in whicheach displaying electrode is connected to each first drain electrodethrough each passivation layer via hole respectively.
 11. The methodaccording to claim 8, wherein a height of the light guiding poles is35%-65% of a distance between the TFT substrate and the transparentelectrode substrate.
 12. The method according to claim 11, wherein theheight of the light guiding poles is 50% of the distance between the TFTsubstrate and the transparent electrode substrate.
 13. The methodaccording to claim 9, wherein a height of the light guiding poles is35%-65% of a distance between the TFT substrate and the transparentelectrode substrate.
 14. The method according to claim 13, wherein theheight of the light guiding poles is 50% of the distance between the TFTsubstrate and the transparent electrode substrate.
 15. The methodaccording to claim 10, wherein a height of the light guiding poles is35%-65% of a distance between the TFT substrate and the transparentelectrode substrate.
 16. The method according to claim 15, wherein theheight of the light guiding poles is 50% of the distance between the TFTsubstrate and the transparent electrode substrate.